Adult frogs have
A. lungs
B. gills
C. lenticels
D. spiracles

(a) only B is correct
(b) both B and D are correct
(c) only A is correct
(d) B, C, and D are correct

Q.

Which of the following statements about cyclic photophosphorylation are correct?

(a) Only PS – I functions

(b) NADPH is formed

(c) Occurs when the light of wavelength beyond 680 nm is available for excitation

(d) Oxygen is evolved

Q.

Read the statements given below and choose the correct statements.

a) Sodium chloride is more soluble in heavy water than in normal water.

b) Heavy water is used to study the reaction mechanism.

c) $A{l}_4$$C_3$ on duterolysis gives duetero methane.

d) Heavy water is more viscous than water.

Q. The stomata take in and give out
(A) hydrogen.
(B) oxygen carbon dioxide, water.
(C) water and oxygen only.
(D) carbon dioxide only.

(a) Only B is correct.
(b) Only A is correct.
(c) Both B and C are correct.
(d) Both B and D are correct.

Q. Given $S=\frac{a^{n+1}+b^{n+1}}{a^n+b^n},a,b>0$
$\left(1\right)S=$ A.M. of $a$ and $b$, if $n=0$
$\left(2\right)S=$ G.M. of $a$ and $b$, if $n=\frac{1}{2}$
$\left(3\right)S=$ H.M. of $a$ and $b$, if $n=-1$, then

Q.

Points A, B and C are taken in such a way that they lie on the same line. Point D does not lie on the line $\overleftrightarrow{AB}$ .

Statement 1: $\angle$ABD and $\angle$DBC are supplementary

Statement 2: $\angle$ABD and $\angle$DBC form a linear pair

Choose the correct option: