What does it mean when a mineral has a definite chemical composition? select 2 choices.
it always occurs in pure gorm.
it always contains certain elements.
it cannot form from living or once living materials.
it always contains elements in definite proportions.
it cannot contain atoms from more than one element.

The mineral has definite composition when it contains elements in definite proportion and it also cannot be formed from living or once lived materials.

A mineral is said to be of definite chemical composition only if it consists of elements in definite proportion or quantity. The chemical composition of mineral would be same with chemical formula. The atoms occur in specific range in each minerals.

The mineral cannot be formed from a living organism or from an organism that once lived. All minerals occur naturally in nature. Minerals cannot be man-made or manufactured in laboratory.

i just calculated it all out, and not including weekends, and all the different days off. as of this school year (2018-2019) students are spending 2198 hours in school this year