14 oz (ounces) is the same as how many lbs (pounds)?

0.875 Pounds

Explanation:

Formula  is

Just divide the mass value by 16

B) a helium nucleus moving at a velocity of 1000 mph

Explanation:

According to the De Broglie relation

λ= h/mv

h= planks constant

m= mass of the body

v= velocity of the body.

As we can see from De Broglie's relation, the wavelength of matter waves depends on its mass and velocity. Hence, a very small mass moving at a very high velocity will have the greatest De Broglie wavelength.

Of all the options given, helium is the smallest matter. A velocity of 1000mph is quite high hence it will have the greatest De Broglie wavelength.