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.
exists and is an alternate of . All silver coins had 10% copper added to make them harder so they would withstand circulation better. Silver was taken out of circulating US coins in 1965 with the exception of the half-dollar which continued to be minted in 40% silver from 1965 until 1970.