Among $K$,$Mg$,$Au$,and $Cu$,the one which is extracted by heating its ore in air is

Four resistors $A, B, C$ and $D$ form a Wheatstone bridge. The bridge is balanced when $C = 100 \ \Omega$. If $A$ and $B$ are interchanged,the bridge balances for $C = 121 \ \Omega$. The value of $D$ is (in $\Omega$)

$A$ very large number of balls are thrown vertically upwards in quick succession in such a way that the next ball is thrown when the previous one is at the maximum height. If the maximum height is $5 \, m$,the number of balls thrown per minute is (take $g = 10 \, m/s^2$).

Which nitrogenous base is present in $RNA$ but not in $DNA$?

$A$ compound absorbs light in the wavelength region $490-500 \ nm$. Its complementary colour is

Which one of the following is wrong for fungi?