The diagram shows a motion map. Which best describes the motion of the object between 1
and 4 seconds?

.
O The object has decreasing acceleration and
increasing velocity
O The object has positive acceleration and eventually
stops.
O The object has decreasing acceleration and
decreasing velocity.
The object has negative acceleration and eventually
stops

Zirconium has an hcp crystal structure and a density of 6.51 g/cm3. (a) what is the volume of its unit cell in m3? (b) if the c/a ratio is 1.593, compute the values of c and a.

The frequency of vibrations of a vibrating violin string is given by f = 1 2l t ρ where l is the length of the string, t is its tension, and ρ is its linear density.† (a) find the rate of change of the frequency with respect to the following. (i) the length (when t and ρ are constant) (ii) the tension (when l and ρ are constant) (iii) the linear density (when l and t are constant) (b) the pitch of a note (how high or low the note sounds) is determined by the frequency f. (the higher the frequency, the higher the pitch.) use the signs of the derivatives in part (a) to determine what happens to the pitch of a note for the following. (i) when the effective length of a string is decreased by placing a finger on the string so a shorter portion of the string vibrates df dl 0 and l is ⇒ f is ⇒ (ii) when the tension is increased by turning a tuning peg df dt 0 and t is ⇒ f is ⇒ (iii) when the linear density is increased by switching to another string df dρ 0 and ρ is ⇒ f is ⇒

What changes occur in the brain during the teenage years? 25 points, someone me out!a.) thinking becomes slower as the brain grows larger. b.) connections between neurons become stronger and faster. c.) unused neurons fuse together to form larger, better functioning neurons. d.) more neurons are developed.