The gestation period for an elephant is 640 to 660 days. This is equivalent to about 95 weeks, or 22 months, and is the longest gestation period of any mammal.
Dimes dated after 1964 are copper-nickel clad and contain no silver. Quarters are also clad, except for the bicentennial commemorative coins with an S mint mark that were produced for mint and proof sets. Kennedy half dollars from 1965 to 1970 were 40 percent silver composition. After 1970, all Kennedy halves were clad, except the same S bicentennial issue.
Dimes, Quarters, half dollars, and dollar coins before 1964 are 90% silver. Also half dollars from 1965-1969 have 40% silver in them. Silver nickels were minted during 1942-1945 and the nickels are only 35% silver. Any other nickels other than those dates aren't silver. Source(s): Have about 5 years experience.