200分求一道物理题 懂英文的神人 If sodium (Na),with an atomic weight of 23,combines with oxygen (O),with an atomic weight of 16,to from the compound Na2O,what is the ratio of the mass of sodium to oxygen that you would expect to react com

200分求一道物理题 懂英文的神人 If sodium (Na),with an atomic weight of 23,combines with oxygen (O),with an atomic weight of 16,to from the compound Na2O,what is the ratio of the mass of sodium to oxygen that you would expect to react com 200分求一道数学题,求懂英文,懂棒球规则的神人解答呀A baseball diamond has four bases (forming a square) that are 90 feet apart; the pitcher's mound is 60.5 feet from home plate.Approximate the distance from the pitcher's mound to 200分求一道数学题,懂英文的来,求神人教下过程A radioactive substance decays accrding to q(t)=q0e^-0.0063t where q0 is the initial amount of the substance ant t is the the in days.Find the half-life of the substance to the nearest ten 最后一道题,求神人 200分求一道物理题,求懂英文的高手来帮下忙A certain isotope has 80 protons and 122 neutrons in its nucleus.Identify the element involved and find the atomic and mass numbers.Atomic number=Mass number= 一道英文(sat2)物理题 求神人解图求神人,传说级神人解图,求图中所有猫的名字. 200分求一道物理题,求帮助 各种求 懂英文的高手嘞Light with a wavelength of 544.6 nm strikes a single slit that is 0.4 mm wide. The diffraction pattern produced by the slit is observed on a wall a distance of 1.4 m from the slit. (a) 200分求一道物理题 求懂英文的高手啊Strontium-89 is a radioactive isotope with an atomic number of 38.How many protons and how many neutrons are present in the nucleus of this isotope?Number of Protons =Number of Neutrons = 200分求一道数学题,求懂英文的高手If a projectile is fired from ground level with an initial velocity of ν ft/sec and at an angle of θ degrees with the horizontal,the range R of the projectile is given by the following formula.If ν = 9 一道简单的物理题 求解释 求一道有关运动的物理题 求一道关于静力学的物理题 一道物理题,关于求电流电阻的. 初三的一道物理题,求大神 求数学神人,数学神人.跪求高中数学特别厉害的数学神人,跪求,跪求. 求一道物理题 一道物理题,求思路