Answer:
Beryllium Fluoride (BeF2) is an ionic compound
The speed of sound is given by the formula
Speed of sound = square root (Young's Modulus/density)
Young's modulus for gold = 78 GPa which is 7.8 * 10^10 Pa
Speed of sound = (7.8 * 10^10 / 19.3 ) = sqrt (4.04 * 10^9 )
Speed of sound = 6.36 * 10^4 m/s <<<=== answer.
Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form cones, or solitary as in yew, Torreya, Ginkgo.