Answer:
Ultrasound is used by bats to navigate (move) and catch prey. Ultrasonic squeaks are produced by bats. These squeaks ponder prey and then return to the bat's ear. This provides bats with information about the location of prey, allowing them to catch it.
Explanation:
Answer:
C
Explanation:
a parallel circuit because there is more than one path
Answer:
r=2.6 cm
Explanation:
Hi!
Lets call steel material 1, and the new alloy material 2. You know their densities:

The volume of a sphere with radius r is given by:
Then the masses of the bearings are:

For the masses to be the same:
![\rho_1 V_1 = \rho_2 V_2\\\frac{V_2}{V_1} =\frac{\rho_1}{\rho_2}\\(\frac{r_2}{r_1})^3 = \frac{8.08}{3.14}=2.57\\r_2=\sqrt[3]{2.57}\;r1 =1.37r_1=1.37*1.9cm=2.6cm](https://tex.z-dn.net/?f=%5Crho_1%20V_1%20%3D%20%5Crho_2%20V_2%5C%5C%5Cfrac%7BV_2%7D%7BV_1%7D%20%3D%5Cfrac%7B%5Crho_1%7D%7B%5Crho_2%7D%5C%5C%28%5Cfrac%7Br_2%7D%7Br_1%7D%29%5E3%20%3D%20%5Cfrac%7B8.08%7D%7B3.14%7D%3D2.57%5C%5Cr_2%3D%5Csqrt%5B3%5D%7B2.57%7D%5C%3Br1%20%3D1.37r_1%3D1.37%2A1.9cm%3D2.6cm)
The answer is D, because the collision's between molecules are elastic, not inelastic.