15. واحدة من الاتي ليست من الخصائص المشتركة
للقطاع الزراعي في الوطن العربي؟
عدم استعمال الأساليب الزراعية
البدائية
ضعف ادارة الموارد المائية
تدني کمية الانتاج الحيواني

option a is correct i.e.

explanation:

in context to the membrane of nerve impulse, the outer membrane of neuron is semi permeable that is only sodium ions can pass through the membrane i.e. smaller ions can pass through the membrane while larger ions cannot pass through it.

the transfer of energy between two molecules spaced just nanometers apart plays a key role in many technologies, including photovoltaics, quantum information systems, lighting, and sensors, as well as in biophysics to measure nanometer distances and in photosynthesis. but an open question in this area is what effect, if any, the surrounding photonic environment has on this nanoscale energy transfer. by designing and performing a carefully controlled experiment to answer this question, scientists have settled the debate and found clues to improving the efficiency of many of the technologies that rely on this process.

explanation:

fabric is silk wool ext. paper isnt

explanation:

u cant make fabric out of paper cause paper comes from wood while fabric comes from animals