Correct Answer: active

Solution : The correct answer is active.

When a host encounters antigens, which could be living or dead microbes or other proteins, the host's body produces antibodies in response. This form of immunity is termed "active immunity." Active immunity is a gradual process and can be either

Correct Answer: $2+\sqrt{3}$

Solution : Given,
$\frac{\cos \theta}{1-\sin \theta}+\frac{\cos \theta}{1+\sin \theta}=4$
⇒ $\frac{\cos\theta(1+\sin\theta)+\cos\theta(1-\sin\theta)}{(1+\sin\theta)(1-\sin\theta)}=4$
⇒ $\frac{\cos\theta+\sin\theta\cos\theta+\cos\theta-\sin\theta\cos\theta}{(1+\sin\theta)(1-\sin\theta)}=4$
⇒ $\frac{2\cos\theta}{1-\sin^2\theta}=4$ [As $\sin^2\theta+\cos^2\theta=1$]
⇒ $\frac{\cos\theta}{\cos^2\theta}=2$
⇒ $\cos\theta=\frac{1}{2}$
⇒ $\theta=60°$
Now, $\sec \theta+\operatorname{cosec} \theta+\cot \theta=\sec60°+\operatorname{cosec}60°+\cot60°$
$=2+\frac{2}{\sqrt3}+\frac1{\sqrt3}$
$=\frac{2\sqrt3+2+1}{\sqrt3}$
$=\frac{2\sqrt3+3}{\sqrt3}$
$=2+\sqrt3$
Hence, the correct answer is $2+\sqrt3$.

Correct Answer: 14 : 3

Solution : Given: A canister holds 36 litres of a mixture of milk and water in a ratio of 3 : 1.
Quantity of milk = $\frac{3}{4} × 36 = 27$
Quantity of water = $\frac{1}{4} × 36 = 9$
After adding 15 litres of

Correct Answer: 16.8

Solution : Given:
84, 42, 28, 21, ?

Let's apply the pattern –
84 ÷ (1 + $\frac{1}{1}$) = 42; 42 ÷ (1 + $\frac{1}{2}$) = 28; 28 ÷ (1 + $\frac{1}{3}$) = 21; 21 ÷ (1 + $\frac{1}{4}$) = 16.8

So, 16.8 is the missing term

Correct Answer: $1$

Solution : $\tan1° \tan2° \tan3°...\tan89°$
$= \tan1° \tan2° \tan3°...\tan45°...\tan(90-3)°\tan(90-2)°\tan(90-1)°$
$=\tan1° \tan2° \tan3°...\tan45°...\cot3°\cot2°\cot1°$
As we know, $\tan\theta=\frac{1}{\cot\theta}$
So, it will cancel out all the terms except $\tan45°$.
$=\tan45°$
$= 1$
Hence, the correct answer is $1$.

Correct Answer: 59

Solution : Given:
$\sqrt[4]{81}$ R 6 P 3 S 26 R 64 = ?

After replacing the letters with the mathematical signs, we get:
= $\sqrt[4]{81}$ + 6 × 3 – 26 + 64
= 3 + 6 × 3 – 26 + 64
= 3 +

Correct Answer: Smallpox

Solution : The correct answer is Smallpox.

Smallpox is a deadly and highly contagious viral disease, caused by the Variola virus and now it is successfully eradicated worldwide, the last known case of smallpox was recorded in 1977 in Ethiopia and it was declared to be

Correct Answer: my these things

Solution : Given:
1. my personal use⇒521
2. use these things⇒169
3. personal things⇒29

By comparing all the above–coded sentences, we find that –
In sentences 1 and 2, use is a common word and 1 is a common code.
In sentences 2 and 3,

Correct Answer: CWX– AVZ

Solution : Let's check each option –
First option:  NVH–KUK; N – 3, V – 1, H + 3 = KUK
Second option REA–ODD; R – 3, E – 1, D + 3 = ODD
Third option: CWX–AVZ; C – 2, W – 1, X +

Correct Answer: 31.58%

Solution : As per the given graph,
The number of girls using smartphones $=180+60+120+20=380$
The number of girls using the smartphones of Nokia $=120$
The required percentage $=\frac{120}{380}×100=31.58$%
Hence, the correct answer is 31.58%.