1. Which of the following statements concerning 'atom' is correct? A. All atoms do not carry net charges. B. Mass is evenly distributed within an atom. C. All atoms consist of protons, neutrons and electrons. D. For all elements, atoms of the same element have the same mass number. (HKDSE 2015 Paper 1A Q15)

Resuelva en términos reducidos \( \frac{12}{16}=\square \)

4. \( V(2 ; 3), W(-3 ; 4) \) and \( Z(1 ;-4) \) are the vertices of \( \triangle V W Z \) and \( V^{\prime}(12 ; 18) \), \( \quad \) 6. If \( \Delta V^{\prime} \) if \( \Delta V^{\prime} \) \( W^{\prime}(-18 ; 24) \) and \( Z^{\prime}(6 ;-24) \) are the vertices of \( \triangle V^{\prime} W^{\prime} Z^{\prime} \). a) State the factor of enlargement. b) Complete the following statements: i) perimeter \( \triangle V W Z: \) perimeter \( \triangle V^{\prime} W^{\prime} Z^{\prime}=\square: \square \) ii) area \( \triangle V W Z: \) area \( \triangle V^{\prime} W^{\prime} Z^{\prime}=\square: \square \).

Find the standard deviation of the sampling distribution of sample means using the given information. Round to one decimal place, if necessary. \[ \mu=56 \text { and } \sigma=10 ; n=9 \]

Suppose that a study of elementary school students reports that the mean age at which children begin reading is 5.3 years with a standard deviation of 0.8 years. Step 1 of 2 : If a sampling distribution is created using samples of the ages at which 32 children begin reading. what would be the mean of the sampling distribution of sample means? Round to two decimal places, if necessary.

1. ENCONTRAR EL PERIMETRO DE UN TERRENO IRREGULAR, QUE TLENE LAS SIGUIENTES ME DIOAS: 400 M 80OM, 500 M Y 50 m . (HACER OPERACIONES)