In normal development, if the male contributes an X chromosome, the child will be male; if he contributes a Y chromosome, the child will be female

The statement, "Nothing in life can be known for certain" is most likely to be uttered for the first time by someone at the ____ stage of reflective judgment

a. first b. second c. fourth d. sixth

According to the variance sum law, the variance of the difference of two independent variables is equal to the difference of their variances

Indicate whether the statement is true or false