GRE
4
k
x+y+z
360
The average (arithmetic mean) of $$\frac{1}{S^{2}}$$, $$\frac{1}{S}$$, $$S$$, and $$S^{2}$$
$$2S$$
$$w^{2}-65w$$
0
$$x$$
65
$$(1)^{5n}$$
$$(1)^{5+n}$$
x
$$(x+y)^{2}$$
144
c
d
25000 +道题目
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