1-5:BDACB

6- 10:ABDCB

1 1- 15: China civil aviation

16-20:AACCD

Short answer questions:

2 1: Galileo and the new moon (new moon)

About 22: 14.4

23: (1) force can deform an object; (2) Liquid can generate buoyancy (or buoyancy will increase with the increase of V rows).

24: (1) Two (2) men

25: (1) Is there nucleation (2) Oxygen in water.

26:3、+4

27: (1) source of infection (2) air or droplets (3) genetic DNA

28: 2kmno4 = = (heating) K2MnO4+MnO2+O2

29: Inhalable particulate matter, 6× (ten to the eighth power), 75%, 4

Experimental inquiry questions:

30: After the test paper is wetted with distilled water, test the PH and hydrochloric acid (or HCl).

3 1: (1) Starch (2) Switch between Step 2 and Step 3 (3) to observe the time required for blue fading (or observe the depth of blue after the same time).

32: (1) Drainage and gas collection method (2) Dad, put the burning match into another bottle of gas and observe the phenomenon.

33: (1) illumination (2) Potato tubers need to grow in the dark.

34: temperature, (omitted) (2) 1506, 1.0 (3) magnetic field direction (or current direction)

Analysis and calculation problems:

35: (1) p = (4 to the tenth power) tile (2)F float = 5× (3 to the 10 power) ox, V row =0.5 cubic meters, V object =0.75 cubic meters (3) solar power supply.

36: (1) The mass of CO2 produced by measuring cylinder (2) is 4.4g, and the mass fraction of CaCO3 is 62.5%.

37: (1) I = 0.023 A, W=0.0 125 kWh (2)B (3) thermoregulatory center.

38: (1) B (2) Dementia (3)B (4)58.98 g (5)4.29 g (6) Timely check the thyroid condition (or reasonable suggestions such as people with high thyroid hormone content should eat less kelp).

& lt end >

Whew, I'm so tired ... some of them don't know how to type, so some of them may be a little difficult to distinguish ... I have several other courses, all of which are correct answers and reference answers. Do you want it?