The unit of time is:

1. light year
2. parsec
3. leap year
4. angstrom

1 Å is equal to:

1. 0.1 nm
2. 10^-10cm
3. 10^-8m
4. 10⁴µ

Light-year is the unit of:

1. Time
2. Length
3. Mass
4. none of these

One solar mass is equal to :

1. 3 x 10²⁰ kg
2. 2 x 10²⁷ kg
3. 2 x 10³⁰ kg
4. 3 x 10³⁰ kg