Choose the biconditional statement with the same meaning as these two statements combined:
statement 1: if a number is positive, then it is greater than zero.
statement 2: if a number is greater than zero, then it is positive.
select one:
a. a number is positive if and only if it is not zero.
b. if a number is positive and greater than zero, then it is not negative.
c. if a number is non-negative, then it is positive.
d. a number is positive if and only if it is greater than zero.

Anyone know? is appreciated! will mark brainliest if correct!

Can someone tell me if this is perpendicular? !

Nthe opening scene of the movie raiders of the lost ark, indiana jones replaces a golden statue with a bag of sand. the platform on which the statue is placed is designed to detect the mass of the statue. if the bag of sand has a different mass than the statue, then a mechanism triggers and destruction ensues. the density of gold is about 20\text{ g/cm}^320 g/cm 3 20, space, g, slash, c, m, start superscript, 3, end superscript. the density of sand can be estimated at 2.5\text{ g/cm}^32.5 g/cm 3 2, point, 5, space, g, slash, c, m, start superscript, 3, end superscript. the gold statue can be modeled as a cylinder with height 25\text{ cm}25 cm25, space, c, m and radius 8\text{ cm}8 cm8, space, c, m. in terms of \piπpi, what is the mass of sand indiana jones needs to avoid triggering the mechanism?