在统计中，常用大写字母来表示随机变量，小写字母来表示随机变量的观测值（样本），一组观测值称为随机变量的一组样本，已知某随机变量及其一组观测值（样本）如下表：现在R语言中计算其样本均值和样本方差，在R语言中计算均值的函数是__________,X的样本均值为__________,(精确到两位小数),计算方差的函数是___________,X的样本方差为__________.
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How can you be _______ to the suffering of starving people?
A. indifferent
B. inevitable
C. peculiar
D. different
The dull party finally ________ when a famous band arrived.
A. came to life
B. came to light
C. came to hand
D. came to mind
The TV program ________the aftermath of the Paris terrorist attacks.
A. attracts
B. appeals
C. highlights
D. fascinates
The house was built in 1980, and has been expanded several times in _______ years.
A. substantial
B. subservient
C. subsidiary
D. subsequent
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