1969-12-30 — Page 22

頁二第張六第日二廿月一十年考巴 WAH KIU YAT PO

報日僑筆

二期星26日十三月二十年九六九一圈公年八十五國民華中 育教僑華

170英文中學會考試題預習專欄

L:70英文中學會考試題預習專欄

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數學科

KATHEMATICS (9)

(九)

Further Examples on Klementary Kensuration

•Example 7. An open cardboard bor, 1 ft. long, 8 in.

wide, 5 in. high, in fitted with a

cardboard lid which covers the top and one of the larger aides and both of the smaller sides. Find the total area of cardboard. required for the box and lid. 8.

Arsa of base = 1 × 12-

Area of larger surfaces – 2 x 1x

Area of smaller surfasen = 2 1/

årna of lid - - + 22 + 3

Total area of cardboard required:

(3 + 2 + § + 38 ) × 144

532 iq.in.

Exaole 8 A piece of wire in in the form of an aro of a circle of radius 10 in., subtending an angle 150 at the centre of the circle, It is bent into the form of a complete cirole) find the radius of this oirols.

x 10 x 150

360

Length of the virs = 2 x

225

550

#

Ai this piece of wire ia bent into the form of a complete cirole;

the circumference of this cirola –

550

Radius of the circle i 550 × 1 × 22 - 4/2 3

Example 9 Find the radius of a circle whose area is

aqual to the sum of the areas of two giroles of radii 3 in., 4 in. respectivelys

Aran of bizole with radius 3"-

Area of circle with radius

2 x 4 x 4 sq. in.

Area of new ciròla » 22 (42+32) Badius of new circle «√ (42 + 32) « 5 in.

Brample 10 The internal section of a tunnel is a

rectangle 24 ft. wide, surmounted by a semicircle, and the greatest height is 20 . Find the total area of the sides

zoof of the tunnel, if it is 50 ya Long.

Radius of semicirale - 12 1

Height of rectangle.

20 - 12 - 8 ft.

Circumference of mani-

x 12

Area of roof m

Ars of sides. x 50 x 2 sq

50 sq.yo

Total area =

50( 22 x 12 + 33 x 2)

895,2 mg.yd.

英文科

(A)

English Language (9)

Answers to Exercise &

Precis

The laying of submarine cables leads to the exploration of the sea-botton which is divided into two zones of water. The terrigenous zone, extending. two or three hundred miles to seaward and being rich of earthy products, is the part where the sea, washes the earth away and the rivers bring down the debris. of the land. While the pelagic or the deep-sea bottom, with its usual depth varying from two to three miles is very different. There is no light and that beyond a certain depth, it is believed, scarcely anything solid will sink. Over the deep-sea bottom, there atretobes a very thick layer of the mixture of rad clay and relics of whale and shark but without. chalk or any of the shell siftings common to those in shallower depths. The red mud, formed by substance ejected by hidden craters under the sea bottom is different from and older than all the substance fouina in the sedimentary rocks. How, messages can be sent from one continent to another at lightning speed. because cables are laid.

ComprehensionT

1. Some mowledge of stars, plants and metals, "2% (a) The notion of proof.

3. (d) They ask so as to learn.

4. (c) Thales

5. (b) That all things are made of the same basio

stuff

The method and procedure of thinking

(e) Anaximander and Pythagoras

The world is in a state of constant change.

Exercise 9.

Choose the most suitable answer, to aach or TAG followings

1. The fierce dog flow. the stranger as the

atranger care near the house, (A) at (B) on (C) against (D) up (E) down

2. He touched the button and the drawer few.

Ho (2) out: (C) open (D) in (F) on

He works hard because he wants to My

(A) away (B) out (C) high (D) low (F) by

4. He had defeated his opponent. He looked at the

people around him with

∙10.

(A) his colour (3) Idw colour (C) off colour

flying colours (E) bloody colour

8

He was

o angry that ha

heazy stonea

fly the pisos of

(A) let (3) made (4) did

(D) tried (E) threw

of the book and tors

(0) fly-trap.

He wrote something on the it off.

(4) rig-leaf (B) fly-papaz (D) fly-wheel

at his opponent suddenly and gave him a heavy blow, (A) lumped (B) lunged (C) lunched (D) lurched We know that he has been scolded by his mother again because he come in with a sorrowful (A) mike (B) mien (C) mimio (D) mimosa

The workman wearily

plads (3) plots

his way home.

(C) plops (D) plows

He entered the kitchen and soon-retunned with some

for the dogs.

Dough-onat (B) rough-dry (C) rough-iga rough-hew

11. He is

(A) soppy (3) sordid: (C) sorrel

...

fer he wually makes foolish mistakes.

(D) aortie 12. She is so lovely because she possesses the

charm. (A) subtle (B) subtend (C) subsidy (D) subside

across the strast. 13. The old drunkard

(A) totem (3) tottered 14. The climate has the

or too cold.

(C) toucun (D) totted of never being too hot

(C) virtues (V) visage. he should arrive here?

(A) virus (3) virulenos

15. Was this the day

__(1) whion (3) when (C) why (D) whose 16. He is one of the famous authors who

Lovele

(A) writem (B) write (C) is writing (0) are writing

17. The window had been broken, We must find someone

and

(A) have it repaired (B) repair it (c) shall repair it: (D) shall have it repaired 18. We greated his warmly

arrival.

(2) on (B) in (C) at (D) by (B) of

profession.

19. Mr. Wong is a butcher

(A) or (D) in (C) at... (D), by (F))TOW

20. He cans and paid a visit to

timer,

(A) on (B) in (C) at- of (E) for

21. I thought of revenging on him but decided to

forgive him. second thoughts. (A)

) of (3) on (0) by (D) in (B) at

22. The dog seemed to be sleeping but

it sprang

at onos (B) all at once (C) once (D) ones one at a time

23. The young girl thought that she would soon be able to find her feat. The phrase underlined maans z

((A) would soon be able to find her shoes

would soon be able to find a job

would soon be able to be independent- would soon be able to run quickly szeugn break the record.

(B) would soon be able to solve the problem in

4. The milly woasanwas trying to keep up with the

The 111 woman trying

Josease. The phrase underline means to keep up with

(A) her frienda:

(B) her neighbours.

(C) the European ladder

Mr. Jones and his family

(D) Mr. J

"Don't waste time beating about the bush,

phrase underlined means

going to hunt (3) playing in the forent

(C) talking round a subject.

doing foolish things

26. When he was asked to explain the situation he

Бесаде

tongue-tied

murmured (C) chattered (D) flattered

27. During the competition, Peter behaved roughly,

But his brother bshaved even *

than he did.

8

(A) more roughly (3) mont roughly (C) wozet (D) more peorly

28. Each of the five boys will throw a stone, They

want to see who can make

distance.

(A) far (8) farther (C) the farthest (D) further

the furthest

29. All four of us can read, but John reads.

more qui okay (3) the most quickly

most quickly

ckly (D) fast (5) faster

30. We see John and Peter on the road. We like the

than the former... later

(3) latter (C) late. (D) latent

Example 11 DP, CQ are the perpendiculars from D,

C10 AB. If DF - 238 yd., CQ = 316 yd,, AP = 95 yd. FQ = 174 ya,, 03 - 82 yd., find in aores the mea

of ABCD

Eres of AAPD - 238 x 95

Ares of ACQB -

316

Area of trap. DPQC (238 + 316)≈ 174

Alternation of the levels - 18+ 14-32 in.

Example 13 5 mi. of paper is wound on to a roller, diameter 6 in., the complete roll being 3 ft. in diameter. Find the thickness of the paper in inches.

Area of cross-section of paper =í (18)2 - 4 (3)2

22 (18 – 3)(18+3) 990 in?

The cross-section of the paper is

a rectangle

5 x 5280 x 12 in. long, t in. deep

Thickness of the paper -

990

0.00312 in.

5 x 5280 x 12

Example 1:4 Find the height of a cone if the area of

the curved surface is 100 squine and the basa-radius $16.4.5 in

238 ± 95 + 316 x 82 + 554 x 174

Area of curved surface of cone w

Area of ABCD =

... The slant length of the sone € -

100 4.5.x

4840

By Fythagoras theorem,

15 acres

The height of the cone h

√( 2007 )2 - (4-5)2

5.46 in

152 7 cc.

The volume of the solid sphere is “nunerically equal to the volume of material.

R

π x 152

The radius of solid sphere - (152)1/3

5.34 om

Example 16 If the surface of a soap bubble increasea

by 21p, find the percentage increase in (i) its diameter, (ii) itë volume.

If the surface area of the bubble 42

Then the increased area of the bubble

(1 + 21%) of 4xr2.

47 x

121

100

47 (11)2

The increased radius = 115 - (1 + 10%) of r

the increased in diameter

Example 12 Water is discharged at 3500 gall. per

nin, from a reservoir of surface area 7200 sq.ft. into one with surface area 5600 sq.ft. The sidem of both reservoirs are vertical planes. By how much does the difference of the levels of the two. surfaces alter in 15 min.? (1 cu.ft. - 64 gall)

3500 1 15

62

Volume changes in 15 min. m.

Level changes in larger reservoir

-8400 cu.ft.

8400

* 14 in.

8400

18 in

Level changes in smaller reservoir. 5800

Sxample 15 The external diameter of a hollow metal

sphere is 12 om, and its thickness is 2 on. Find the radius of a solid sphere made of the same material and having the some weight as the hollow: sphere.

Volume of materi

#7 [63 - 43]

(ii) The increased volume

TR3

· [(1 + 10%) of =]3

-73 (1)3

(1 + 33.1%) or #π x3)

increase in volume - 33.1%