Consider the following statement about nuclear fusion reactors.
1. They work on the principle of fission of heavy nuclei.
2. They usually have Tokamak design.
3. They operate at very high temperature

. . . . . . . . invented Atom Bomb.

A. J Robert Oppenheimer

B. John Bau a Ning

C. Samuel Cohan

D. Samuel Colt

Positive rays were discovered by

A. Thomson

B. Goldstein

C. W-Crookes

D. Rutherford

Cathode rays are

A. positive rays

B. neutral rays

C. helium rays

D. electron waves

X-ray can be produced

A. when low speed electrons is ejected

B. when high speed electron is obstructed by a metal surface

C. when anode-ray obstructed by a solid object

D. when γ-ray is obstructed by a solid object