A river is 4.1 km wide. A bridge built across it has 1/7 of its length on one bank and 1/8 of its length on the other bank. What is the total length of the bridge?

• 5.1 km

• 4.9 km

• 5.6 km

• 5.4 km

OA, OB, and OC are radii of the quarter circle shown in the figure. AB is also equal to the radius.

What is angle OCB?

• 60°

• 75°

• 55°

• 65°

383.

Two iron spheres of radii 12 cm and 1 cm are melted and fused. Two new spheres are made without any loss of iron. Their possible radii could be

• 9 and 4 cm

• 9 and 10 cm

• 8 and 5 cm

• 2 and 11 cm

A man buys alcohol at Rs. 75/cL, adds water and sells it at Rs. 75/cL making a profit of 50%. What is the ratio of alcohol to water?

• 2:!

• 1:2

• 3:2

• 2:3

The sum of the digits of a two-digit number is 9. If the fraction formed by taking 9 less than the number as numerator and 9 more than the number as the denominator is 3/4, what is the number?

• 36

• 63

• 45

• 54

The distance between X and Y is 1000 km. A person flies from X at 8 AM local time and reaches Y at 10 AM local time. He flies back after a halt of 4 hours at Y and reaches X at 4 PM local time on the same day. What is his average speed for the duration he is in the air?

• 500 km/ hour

• 250 km/ hour

• 750 km/ hour

• Cannot be calculated with the given information.

If a person travels x% faster than normal, he reaches y minutes earlier than normal. What is his normal time of travel?

• $\left(\frac{100}{\mathrm{x}} + 1\right) \mathrm{y} \mathrm{minutes}$

• $\left(\frac{\mathrm{x}}{100} + 1\right) \mathrm{y} \mathrm{minutes}$

• $\left(\frac{\mathrm{y}}{100} + 1\right) \mathrm{x} \mathrm{minutes}$

• $\left(\frac{100}{\mathrm{y}} + 1\right) \mathrm{x} \mathrm{minutes}$

A and B walk up an escalator one step at a time, while the escalator itself moves up at a constant speed. A walks twice as fast as B. A reaches the top in 40 steps and B in 30 steps. How many steps of the escalator can be seen when it is not moving?

• 30

• 40

• 50

• 60

Which of the following mutagens is most likely to result in a single amino acid change in a gene product?

• Acridine orange

• X-rays

• Ethylmethane sulphonate (EMS)

• Ethidium bromide

Which one of the following analytical techniques does not involve an optical measurement?

• ELISA

• Microarray

• Flow cytometry

• Differential Scanning Calorimetry