# Posts by denis

Total # Posts: 48

Physics
A boat, which can travel 2.30m/s in still water is in a stream with a current moving at 1.20m/s. if the boat is pointed directly across the stream, determine the velocity of the boat relative to the shore?

math
on a print with a scale of 1/4"=1',the scale drawing of the living room us 5"by 6".The dimensions of the actual room will be___________ft.by_________ft.?

Science
If a piece of paraffin wax has a mass of 900g and density of 9g/cm3, if the wax was melted to the liquid state approximately what would its volume be?? HELP PLEASE!!!

math
distance =timeÃ—speed (X-20)(3.25)=2x+30 3.25x-2x=30+65 1.25=95 95Ã·1.25=76

Geometry
Find 2 cos(x/2) sin(x/2) when x = -π/6. I know that cos(x/2) = +- sqrt(1-cosx)/2 and sin(x/2) = +- sqrt(1+cosx)/2, but how to use this identity I'm not entirely sure. Please help.

Chemistry
indium-115 has a half life of 4.5 hours, if you start with a 12.0mg sample of indium-115, how much will remain after 13.5 hours

biology
how can you recognize carbohydrates from a list of biological molecules

b
how can a disaccharide be produced from two monosaccharides

biological
how can a disaccharide be produced from two monosaccharides

biology
how can you recognize carbohydrates from a list of biological molecules

microbiology
what is sugar fermentation

sociology
examine the latent and manifest functions ( of the US response to 9/11. Consider how the emerging structures of society are functional and/or dysfunctional for the nation.

sociology
examine the latent and manifest functions ( of the US response to 9/11. Consider how the emerging structures of society are functional and/or dysfunctional for the nation.

chemistry
The density of ethyl ether is 0.713g/ml would 536.8 g of this anesthetic fit into a 750.0ml flask?explain

biology
a) What type of bond is involved in complementary base pairing? -------------------------------------------------------- b) On what site of the large ribosomal subunit does the second tRNA attach during translation...

biology
1) What is the complementary strand of the DNA sequence GCAAT? a) GGCTT b) CGTTA c) CGTAT d) GCUUA

biology
which of the following represents the F1 generation of a monohybrid cross of YY x yy parents? a)100%Yy b)75%Yy:25%YY c)25%Yy:75%yy d)100%yy

biology
a disease caused by a bb gene is said to be?

chemistry
6). Which solution has the lowest pH? A) 1.3 X10–8 M –OH B) 1.0 X 10–7 M –OH C) 5.1 X10–5 M –OH D) 3.9 X 10–8 M –OH E) 2.3 X 10–3 M –OH

chemistry
7). The pH of a solution is 2.89. What is the [H3O+]? A) 1.3 X10–3 M H3O+ B) 1.3 X 1012 M H3O+ C) 7.9 X101 M H3O+ D) 7.9 X 10–13 M H3O+ E) 1.9 M H3O+

chemistry
8). What is the pH of a fruit with a [–OH] = 3.2  10–9 M –OH? A) 10.5 B) 8.49 C) 3.51 D) 3.5

chemistry
9). What is the balanced equation for the acid–base reaction of nitrous acid with lithium hydroxide? LiOH(aq) + HNO3(aq)  H2O(l) + LiNO3(aq) Li(OH)2(aq) + 2 HNO3(aq)  2 H2O(l) + Li(NO3)2(aq) LiOH(aq) + HNO2(aq)  H2O(l) + LiNO2(aq) 2 LiOH(aq) + ...

chemistry
10). What is the molarity of an HCl solution if 42.5 mL of a 0.110 M KOH solution is needed to titrate a 25.0-mL sample of the acid? A) 0.187 M HCl B) 0.587 M HCl C) 0.0647 M HCl D) 5.35 M HCl E) 1.70 M HCl

chemistry
The [H3O+] in a wine bottle is 3.1  10–2 M. What is the [–OH] in this wine?

chemistry
summarize the solubilty behavior of hydrocarbons in water (a polar solvent) and in non polar organic solvents

chemistry
write the equations for the substitution reaction of methene with bromine under the following conditions. a) reaction in the presence of sunlight CH4+Br2 sunlight=? b) reaction in the absence of sunlight CH4+Br2 =?

chemistry
write the equations for the addition reaction of ethene with bromine under the following conditions. a) reaction in the presence of sunlight H2C=CH2+Br2 sunlight=? b) reaction in the absence of sunlight H2C=CH2+Br2=?

chemistry
what gas is produced in the reaction between calcium carbide and water?write the balanced equation for the reaction.

chemistry
which solution has the lower pH? a)0.1 M HCL or 0.1 M HC2H3O2? b)0.1 M NaOH or 0.1 M NH3? c)0.1 M Na2CO3 or 0.1 M NaCl?

chemistry
DOES Mg(OH)2 HAVE A pH greater than 7 or less than 7

chemistry
DOES H3PO4 HAVE A pH greater than 7 or less than 7

chemistry
WHAT PROPERTY OF SOLUTION IS DESCRIBED BY ITS pH?

chemistry
what is the molarity of a solution prepared by dissolving 2.24 grams of NaOH in enough deionized water to obtain 500.0ml of solution?The molar mass of NaOH is 40.0g

chemistry
calculate the molarity of acetic acid in a vinegar sample,knowing that 5.00ml of vinegar requires 43.50ml of 0.105 M NaOH to just reach the phenolphthalein endpoint in a titration

chemistry
what is the molarity of a solution prepared by dissolving 2.24 grams of NaOH in enough deionized water to obtain 500.0ml of solution?The molar mass of NaOH is 40.0g

chemistry
calculate the molarity of acetic acid in a vinegar sample,knowing that 5.00ml of vinegar requires 43.50ml of 0.105 M NaOH to just reach the phenolphthalein endpoint in a titration

chemistry
write the balanced formula equation and the net ionic equation for the reaction of sodium hydroxide with hydrochloric acid. Formula equation.............. net equation.............

chemistry
How many grams of carbon disulfide,CS2 will form if 0.450 mol of carbon is consumed in a 3C+2SO2=CS2 +2CO2 reaction

chemistry
How many grams of carbon disulfide,CS2 will form if 0.450 mol of carbon is consumed in a 3C+2SO2=CS2 +2CO2 reaction

chemistry
show how CH4 +O2=CO2+H2O obeys the law of conservation of mass

chemistry

Statistics
company claims 10% are green. suppose that candies are packaged randomly into samll bags of 50. school children studying percent open several bags, count colors and find the proportion that are green. a. is the Normal model appropriate here? explain b. where is the center? ...

Math
What is the value of the expression below? 3•(-4)^2