定义在R上的奇函数f(x)，当$x\ge 0$时，$f\left(x\right)=\left\{\begin{array}{c}{\log }_{\frac{1}{2}}(x+1),x\in 0,1)\\ 1-|x-3|,x\in 1,+\infty )\end{array}\right.$，则函数F(x)=f(x)-a(0<a<1)的所有零点之和为（   ）

____cm

    5000 B.C.— People began to farm along the Nile River in Egypt.

    2950B.C. — Egypt was first united under MENES.

    2600B.C. — The first pyramid of Egypt, the Pyramid of Djoser, was built.

    2500 B.C. — The great Pyramid of Gina was built.

    2000 B.C. — The Bantu Peoples began to migrate into central and southern Africa.

    1279 B.C. — Rameses II became pharaoh（法老）of Egypt.

    1070 B.C. — The kingdom of Kush gained its independence from Egypt.

    814 B.C. — The city of Carthage was established by the Phoenician Empire.

    715 B.C. — Kush conquered Egypt and ruled it until 662 B.C.

    650 B.C. — Cathage became independent. It grew into one of the most powerful cities on the Mediterranean Sea.

    590 B.C. — The capital of Kush was moved from Napata to Meroe.

    525 B.C. — The Persians conquered Egypt.

    332 B.C. — The Greeks led by Alexander the Great conquered Egypt.

    264 B.C. — Carthage fought in the First Punic War.

    146 B.C. —Cathage was defeated by Rome. Roman forces destroyed the city.

    30 B.C. — Cleopatra VII, the last pharaoh of Egypt, died. Egypt became part of Rome.