A sentence/a part of the sentence is underlined. Four alternatives are given to the underlined part which will improve the sentence. Choose the correct alternative and click the button corresponding to it. In case no improvement is needed, click the button corresponding to "No improvement". The sales boy told the consumer not to touch the products on display.
Theodore Maiman built the first working laser using a ruby rod while working at Hughes Research Laboratories in Malibu, California. It lased for the first time on May 16, 1960.
3. Who was the first Indian to be President of UN General Assembly?
Spontaneous emission is what you see with most "glow in the dark" toys. You excite the toy by exposing it to bright light, then the toy glows in the dark by spontaneously emitting photons as the excited atoms relax back down to their normal state.
10. Who headed the first scientific group to leave for Antarctica in 1982?