There are nearly about 75000 enzymes of 3 classes are there in the human body. They are : 1. Metabolic Enzymes - Enzymes that help to run our Bodies 2. Digestive Enzymes - Enzymes that help in digesting Food 3. Food Enzymes - Enzymes from raw foods that start our Food digestion.

Answer: D) All the above Explanation: Viruses are responsible for some of the most dangerous and deadly diseases including influenza, ebola, rabies and smallpox. Despite their potential to kill, these potent pathogens are in fact considered to be non-living.   Reasons: 1. Viruses don't have any cells, like living organisms do. They have protein coats but no organelles or other cellular machinery. Just a little DNA packet. 2. Viruses can't produce new proteins, DNA, or RNA and therefore are unable to reproduce on their own. They need infected cells' machinery to make all of these and produce new virons. 3. Viruses have no metabolic activity. They don't use or convert energy and have no ongoing interior processes. They're basically just inert structures until they impact a potential host cell.

Answer: C) 2 Explanation: Total money decided to contribute = 750 x 12 = 9000 Let 'b' boys dropped The rest paid 150/- more => (12 - b) x 900 = 9000 => b = 2 Hence, the number of boys who dropped out is 2.

Answer: B) 3 Explanation: Nitrogen (N2) forms Three Covalent Bonds to become stable.   Here the Atmomic Number of Nitrogen is 7. Because there are 2 electrons in the first orbital and 5 in the second and you still have space for 3 more. So it shares, 3 to get the stable octet. Therefore, there are 3 covalent bonds in N2.

Answer: A) 400 Explanation: Let the total number of pages in the book be 'x'. From given data, 2x/5 + 34x/100 + 52 + 52 = x => 40x + 34x + 10400 = 100x => 26x = 10400 => x = 400. Hence, total pages in the book are 400.

Answer: A) Phnom Penh Explanation: Cambodia Capital- Phnom Penh, Currency- Cambodian riel.

Answer: A) 8, 72 yrs Explanation: Let the present ages be K,M Given K/M = 4/5 5K - 4M = 0 ......(1) Also given that, M - (K + 5) = 3 M - K = 8 .........(2) Then, by solving (1) & (2) M = 40 yrs and K = 32 yrs Hence, Total of ages = 40 + 32 = 72 yrs Difference of ages = 40 - 32 = 8 yrs.

Answer: A) 87400 Explanation: Let X be the total amount with Ramesh Given 28% of X = Cash remaining => Amount spent = 72% of X = 38460 + 24468 = 62928 => 72% of X = 62928 =>  X = ? => X = 87400