2.3* 100*3. 14*5^2=23550cm^3

23550 * 7.8 = 183690g = 183.69kg

3.6.28*0.2= 1.256m^3= 1256l

1256*0.73=9 16.88kg

4.4 * 0.6 * 3.14 * 3.3 *16 = 397.9008 yuan.

5.3 1.4/3. 14 = 10cm

10/2 = 5cm

3. 14*5^2* 15= 1 177.5cm^3

6.3/2 =1.5cm.

3^3- 1/3*3. 14* 1.5^2*3= 19.935dm^3

1.30; 90

2. 18

The questions are simple, but some of them are many.