In order to find the efficiency first we will find the Change in Potential energy of the small stone that robot picked up
First we will find the mass of the stone
As it is given that stone is spherical in shape so first we will find its volume



Now it is given that it's specific gravity is 10.8
So density of rock is

mass of the stone will be



now change in potential energy is given as

here
g = gravity on planet = 0.278 m/s^2
H = height lifted upwards = 15 cm


Now energy supplied by internal circuit of robot is given by

V = voltage supplied = 10 V
i = current = 1.83 mA
t = time = 12 s


Now efficiency is defined as the ratio of output work with given amount of energy used


so efficiency will be 23 %
Answer;
B. Each daughter cell receives its own copy of the parent cell's DNA.
Explanation;
Cell division is the process in which a parent cell divides, giving rise to two or more daughter cells. It is an essential biological process in many organisms.
There are two types of cell division. Mitosis is used for growth and repair and produces diploid cells identical to each other and the parent cell. Meiosis is used for sexual reproduction and produces haploid cells different to each other and the parent cell.
Answer:
As we are converting 220V AC into a 5V DC, first we need a step-down transformer to reduce such high voltage. Here we have used 9-0-9 1A step-down transformer, which convert 220V AC to 9V AC. In transformer there are primary and secondary coils which step up or step down the voltage according to the no of turn in the coils.
Selection of proper transformer is very important. Current rating depends upon the Current requirement of Load circuit (circuit which will use the generate DC). The voltage rating should be more than the required voltage. Means if we need 5V DC, transformer should at least have a rating of 7V, because voltage regulator IC 7805 at least need 2V more i.e. 7V to provide a 5V voltage.
Answer : The correct option is, (D) 278 K
Explanation :
We are given temperature
.
Now the conversion factor used for the temperature is,

where, K is kelvin and
is Celsius.
Now put the value of temperature, we get

Therefore, the temperature 278 K is equal to the 
Answer:
2 charges of electron (2C)
Explanation:
I = Q/t
2 = Q/1
Q = 2×1= 2C
Q = 2 charge of electron