Improvement in Food Resources — Science STD 9 — Question

With increase in surface area,

When a cell is placed in a medium, and it increases in size, the external medium is:

Daytime temperature of moon is:

1. 60°C
2. 70°C
3. 90°C
4. 110°C

Evaporation is indirectly proportional to ___________?

Chlorofluorocarbons have been in use for:

1. Aerosol propellants.
2. Formation of foam.
3. Refrigerators.
4. All the above.

The number of valence electrons in a sulphide ion, S^2-, is:

1. 16
2. 10
3. 9
4. 8

On what factor does speed of wave depends:

The principal cereal crop of India is:

Xylem is made of:

1. Tracheids
2. Vessels
3. Both of these
4. None of these

Howis a bacterial cell different from an onion peel cell?