Multiple choice question: C C

Fill in the blanks: (4) two, four (5)-2 (6) y = 90/x (x >; 0)

Solution: 7. (1) Draw by yourself, in the first quadrant.

(2) let I = k/r.

Substitute R=2 and I=6.

6=K/2

K= 12

∴I= 12/R

(3) When I= 1.5

0.5= 12/R

R=24

A: It is 24 ohms.

8.( 1) Let p = k/v.

Substitute P= 123 and V=0.8.

120=k/0.8

k=96

∴P=96/v

(2) when P= 140

140=96/v

v=24/35

∴V≥24/35

Answer: Not less than 24/35m? .

9.( 1) Let p = k/s.

Substitute P=400 and S= 1.5.

400=K/ 1.5

K=600

∴P=600/S

The value range of independent variable s: S>0.

(2) when S=0.2

p=600/0.2

p=3000

A: It's 3000 Pa.

(3) when P=6000

6000 = 600/ sec

s=0. 1

∴S≥0. 1

A: At least 0. 1㎡.

I was exhausted from playing. What is the third chapter about testing and evaluation? Report pages or give questions.