(4) Images and attributes

[homework] 1, c

2、B

3. Inverse proportional function y=20/x

4 、( 1)t=25/v

(2)25/3 mu

5. (1) ∫ The length of AD is XM, the length of DC is ym, and the area of rectangular ABCD is 60 m? ,

? Xy= 60, that is, y = 60/X.

(2)∵y=60/x, and both x and y are positive integers,

? X can be 1, 2,3,4,0,6, 10, 12,15,20,30,60.

∫2x+y？ 26，& lty？ 12,

? When x=5, y= 12 and x=6,

y = 10； When x= 10 and y =6,

? There are three enclosure schemes that meet the requirements: AD=5 m, DC =12 m;

AD=6 m，DC = 10m； AD = 10/0m, DC = 6m.

[Homework ]6, b

7、C

8、( 1) 32

(2) 12.8

9、v=500/t 125

10, (1) 600km

(2)t = 600/v(v & gt； 0)

(3)8 hours

(4)120km/h

1 1, (1) 10 hour

(2)k=2 16

(3) When x= 16, y = 216/16 =13.5.

? When x= 16, the temperature in the greenhouse is about 13.5℃