1. Geologists use physical properties to identify minerals. For example, the blank cleavage, color, fracture, hardness, luster, specific, gravity, streak, texture

The correct answer is - crystal form (external shape).

Explanation:

Physical properties are used for the identification of the minerals that include specific gravity, streak, texture, luster color, hardness, cleavage, and crystal form.

The most common physical property of the minerals in crystal form or external shape of the mineral. This is the property of the mineral that gives an idea about the homogenous possessing a 3-D internal order.

answer; //the above statement is (false);

the answer is; comparing the frequency of collisions with and without the device

this makes the anti-collision system an independent variable and the collisions a dependent variable. if there are fewer collisions with an anti-collision system that without, then it can be stated that the system is a success. essentially, collisions under an anti-collision system are compared with the frequency of collisions by cars with the human drivers.