What will happen to the current in a circuit,if its resistance is doubled?

$A$ heater is joined in parallel with a $60\, W$ bulb and connected to the mains. If the $60\, W$ bulb is replaced by a $100\, W$ bulb,will the rate of heat produced by the heater be more,less,or remain the same?

State the formula correlating the electric current flowing in a conductor and the voltage applied across it. Also, show this relationship by drawing a graph. What would be the resistance of a conductor, if the current flowing through it is $0.35 \ A$ when the potential difference across it is $1.4 \ V$?

The electric current flowing through any conductor is directly proportional to the electric potential difference across the conductor. Which law is this?

The $I-V$ graphs of two resistors,and their series combination,are shown below. Which one of these graphs represents the series combination of the other two? Give reasons for your answer.

Two bulbs $A$ and $B$ are rated as $90 \, W - 120 \, V$ and $60 \, W - 120 \, V$ respectively. They are connected in parallel across a $120 \, V$ source. Find the current in each bulb. Which bulb will consume more energy?