516: Consider the following crops :
1. Cotton
2. Groundnut
3. Rice
4. Wheat
Which of these are Kharif crops?
(a) 1 and 4
(b) 1, 2 and 3
(c) 2 and 3 only
(d) 2, 3 and 4
517: Two richest known sources of edible protein are
(a) Meat and eggs
(b) Some algae and other micro organisms
(c) Soyabean and groundnut
(d) Milk and leafy vegetables
518: Tim Montgomery set a new world record at the IAAF Grand Prix final in the year 2002 in
(a) Long Jump
(b) 110 m Hurdle Race
(c) 100 m Dash
(d) High Jump
519: Which of the following leaf modifications occur(s) in the desert areas to inhibit water loss?
1. Hard and waxy leaves
2. Tiny leaves
3. Thorns instead of leaves
Select the correct answer using the code given below :
(a) 2 and 3 only
(b) 2 only
(c) 3 only
(d) 1, 2 and 3
520: Total internal reflection can take place when light travels from
(a) diamond to glass
(b) water to glass
(c) air to water
(d) air to glass