GWD 数学题请教

A set of numbers has the property that for
any number t in the set, t + 2 is in the set. 
If –1 is in the set, which of the following must also be in the set? （D）

        

I.                   
-3         II.                
1         III.              
5

A.    I only

B.    II only

C.    I and II only

D.    II and III only

E.    I, II, and III

A photographer
        will
arrange 6 people of 6 different heights for photograph by placing them in two
rows of three so that each person in the first row is standing in front of
someone in the second row.  The heights
of the people within each row must increase from left to right, and each person
in the second row must be taller than the person standing in front of him or
her.  How many such arrangements of the 6
people are possible? （A） 

A.      5

B.      6

C.      9

D.     24

E.      36

June 25, 1982, fell on a Friday.  On which day of the week did June 25, 1987,
fall?  (Note: 1984 was a leap year.) （E）

A.      Sunday

B.      Monday

C.      Tuesday

D.     Wednesday

E.      Thursday