The first known practically functioning telescope was invented in __________ at the beginning of the 17th Century.
a) U.S.A
b) U.S.S.R
c) Netherland
d) England
Each surface of a lens is a part of a sphere, the center of which is called as:
a) Optical Center
b) Center of Curvature
c) Focal point
d) Principal focus
A typical human chromosome contains _____ millions nucleotides in its DNA.
a) 140
b) 150
c) 160
d) 170
An average adult human body has about_______ liters of blood.
a) 4
b) 5
c) 6
d) 7
__________ is the only disease that has been completely wiped out throughout the world.
a) Small pox
b) Chicken pox
c) Measles
d) Cholera
Explanation: Before smallpox was eradicated, it was a serious infectious disease caused by the variola virus. It was contagious meaning, it spread from one person to another. People who had smallpox had a fever and a distinctive, progressive skin rash.
Thanks to the success of vaccination, smallpox was eradicated, and no cases of naturally occurring smallpox have happened since 1977. The last natural outbreak of smallpox in the United States occurred in 1949.
Natural gas consists primarily of:
a) Methane
b) Ethane
c) Butane
d) Propane
