When a certain weight is suspended from a long uniform wire,its length increases by $1 \ cm$. If the same weight is suspended from another wire of the same material and length but having a diameter half of the first one,the increase in length will be ......... $cm$.

$A$ vertical spring with force constant $K$ is fixed on a table. $A$ ball of mass $m$ at a height $h$ above the free upper end of the spring falls vertically on the spring so that the spring is compressed by a distance $d$. The net work done in the process is

Identify the blank spaces $a, b, c$ and $d$ given in the following table and select the correct answer.
| Organism | Type | Product |
| :--- | :--- | :--- |
| $a$ | $b$ | Cyclosporin-$A$ |
| $c$ | Bacterium | Butyric acid |
| $d$ | Bacterium | Lactic acid |

Which of the following is related to genetic engineering?

Which of the following is a non-living level of biological organization?

Three taps $A, B, C$ fill up a tank independently in $10 \, h$,$20 \, h$,and $30 \, h$,respectively. Initially,the tank is empty. Exactly one pair of taps is open during each hour,and every pair of taps is open for at least one hour. What is the minimum number of hours required to fill the tank?