4 1 industry

1.

3.8+7.29= 1 1.09 10. 1-2. 17=7.93 25-0.34=24.66

2.

3x3=9 (species) a: ...

3.

3+2+ 1=6 (field)

4.

2+ 1=3 (species) a: ...

12+8=20 yuan 12+ 15=27 yuan 15+8= 13 yuan.

42 leaves

1( 1).6

(2)6x6=36(dm2) A: the maximum area is 36dm2.

2.6 types

( 1) 15

(2) 10 species

I have been on the phone for half an hour. Take it.